[ifcnv] Use unique_ptr in IfConversion. NFC

[rnk]

lgtm

lib/CodeGen/IfConversion.cpp

private:
     bool ValidSimple(BBInfo &TrueBBI, unsigned &Dups,
                      BranchProbability Prediction) const;
     bool ValidTriangle(BBInfo &TrueBBI, BBInfo &FalseBBI,
                        bool FalseBranch, unsigned &Dups,
                        BranchProbability Prediction) const;
     bool ValidDiamond(BBInfo &TrueBBI, BBInfo &FalseBBI,
                       unsigned &Dups1, unsigned &Dups2) const;
     void ScanInstructions(BBInfo &BBI);
-    void AnalyzeBlock(MachineBasicBlock *MBB, std::vector<IfcvtToken*> &Tokens);
+    void AnalyzeBlock(MachineBasicBlock *MBB,
+                      std::vector<std::unique_ptr<IfcvtToken>> &Tokens);
     bool FeasibilityAnalysis(BBInfo &BBI, SmallVectorImpl<MachineOperand> &Cond,
                              bool isTriangle = false, bool RevBranch = false);
-    void AnalyzeBlocks(MachineFunction &MF, std::vector<IfcvtToken*> &Tokens);
+    void AnalyzeBlocks(MachineFunction &MF,
+                       std::vector<std::unique_ptr<IfcvtToken>> &Tokens);
     void InvalidatePreds(MachineBasicBlock *BB);
     void RemoveExtraEdges(BBInfo &BBI);
     bool IfConvertSimple(BBInfo &BBI, IfcvtKind Kind);
     bool IfConvertTriangle(BBInfo &BBI, IfcvtKind Kind);
     bool IfConvertDiamond(BBInfo &BBI, IfcvtKind Kind,
                           unsigned NumDups1, unsigned NumDups2);
     void PredicateBlock(BBInfo &BBI,
                         MachineBasicBlock::iterator E,
private:
     }
 
     // blockAlwaysFallThrough - Block ends without a terminator.
     bool blockAlwaysFallThrough(BBInfo &BBI) const {
       return BBI.IsBrAnalyzable && BBI.TrueBB == nullptr;
     }
 
     // IfcvtTokenCmp - Used to sort if-conversion candidates.
-    static bool IfcvtTokenCmp(IfcvtToken *C1, IfcvtToken *C2) {
+    static bool IfcvtTokenCmp(const std::unique_ptr<IfcvtToken> &C1,
+                              const std::unique_ptr<IfcvtToken> &C2) {
       int Incr1 = (C1->Kind == ICDiamond)
         ? -(int)(C1->NumDups + C1->NumDups2) : (int)C1->NumDups;
       int Incr2 = (C2->Kind == ICDiamond)
         ? -(int)(C2->NumDups + C2->NumDups2) : (int)C2->NumDups;
       if (Incr1 > Incr2)
         return true;
       else if (Incr1 == Incr2) {
         // Favors subsumption.
if (FnNum < IfCvtFnStart || (IfCvtFnStop != -1 && FnNum > IfCvtFnStop)) {
     DEBUG(dbgs() << " skipped\n");
     return false;
   }
   DEBUG(dbgs() << "\n");
 
   MF.RenumberBlocks();
   BBAnalysis.resize(MF.getNumBlockIDs());
 
-  std::vector<IfcvtToken*> Tokens;
+  std::vector<std::unique_ptr<IfcvtToken>> Tokens;
   MadeChange = false;
   unsigned NumIfCvts = NumSimple + NumSimpleFalse + NumTriangle +
     NumTriangleRev + NumTriangleFalse + NumTriangleFRev + NumDiamonds;
   while (IfCvtLimit == -1 || (int)NumIfCvts < IfCvtLimit) {
     // Do an initial analysis for each basic block and find all the potential
     // candidates to perform if-conversion.
     bool Change = false;
     AnalyzeBlocks(MF, Tokens);
     while (!Tokens.empty()) {
-      IfcvtToken *Token = Tokens.back();
+      std::unique_ptr<IfcvtToken> Token = std::move(Tokens.back());
       Tokens.pop_back();
       BBInfo &BBI = Token->BBI;
       IfcvtKind Kind = Token->Kind;
       unsigned NumDups = Token->NumDups;
       unsigned NumDups2 = Token->NumDups2;
 
-      delete Token;
-
       // If the block has been evicted out of the queue or it has already been
       // marked dead (due to it being predicated), then skip it.
       if (BBI.IsDone)
         BBI.IsEnqueued = false;
       if (!BBI.IsEnqueued)
         continue;
 
       BBI.IsEnqueued = false;
while (!Tokens.empty()) {
         break;
     }
 
     if (!Change)
       break;
     MadeChange |= Change;
   }
 
-  // Delete tokens in case of early exit.
-  while (!Tokens.empty()) {
-    IfcvtToken *Token = Tokens.back();
-    Tokens.pop_back();
-    delete Token;
-  }
-
   Tokens.clear();
   BBAnalysis.clear();
 
   if (MadeChange && IfCvtBranchFold) {
     BranchFolder BF(false, false, *MBFI, *MBPI);
     BF.OptimizeFunction(MF, TII, MF.getSubtarget().getRegisterInfo(),
                         getAnalysisIfAvailable<MachineModuleInfo>());
   }
bool IfConverter::FeasibilityAnalysis(BBInfo &BBI,
   }
 
   return true;
 }
 
 /// AnalyzeBlock - Analyze the structure of the sub-CFG starting from
 /// the specified block. Record its successors and whether it looks like an
 /// if-conversion candidate.
-void IfConverter::AnalyzeBlock(MachineBasicBlock *MBB,
-                               std::vector<IfcvtToken*> &Tokens) {
+void IfConverter::AnalyzeBlock(
+    MachineBasicBlock *MBB, std::vector<std::unique_ptr<IfcvtToken>> &Tokens) {
   struct BBState {
     BBState(MachineBasicBlock *BB) : MBB(BB), SuccsAnalyzed(false) {}
     MachineBasicBlock *MBB;
 
     /// This flag is true if MBB's successors have been analyzed.
     bool SuccsAnalyzed;
   };
 
if (CanRevCond && ValidDiamond(TrueBBI, FalseBBI, Dups, Dups2) &&
       // Diamond:
       //   EBB
       //   / \_
       //  |   |
       // TBB FBB
       //   \ /
       //  TailBB
       // Note TailBB can be empty.
-      Tokens.push_back(new IfcvtToken(BBI, ICDiamond, TNeedSub|FNeedSub, Dups,
-                                      Dups2));
+      Tokens.push_back(llvm::make_unique<IfcvtToken>(
+          BBI, ICDiamond, TNeedSub | FNeedSub, Dups, Dups2));
       Enqueued = true;
     }
 
     if (ValidTriangle(TrueBBI, FalseBBI, false, Dups, Prediction) &&
         MeetIfcvtSizeLimit(*TrueBBI.BB, TrueBBI.NonPredSize + TrueBBI.ExtraCost,
                            TrueBBI.ExtraCost2, Prediction) &&
         FeasibilityAnalysis(TrueBBI, BBI.BrCond, true)) {
       // Triangle:
       //   EBB
       //   | \_
       //   |  |
       //   | TBB
       //   |  /
       //   FBB
-      Tokens.push_back(new IfcvtToken(BBI, ICTriangle, TNeedSub, Dups));
+      Tokens.push_back(
+          llvm::make_unique<IfcvtToken>(BBI, ICTriangle, TNeedSub, Dups));
       Enqueued = true;
     }
 
     if (ValidTriangle(TrueBBI, FalseBBI, true, Dups, Prediction) &&
         MeetIfcvtSizeLimit(*TrueBBI.BB, TrueBBI.NonPredSize + TrueBBI.ExtraCost,
                            TrueBBI.ExtraCost2, Prediction) &&
         FeasibilityAnalysis(TrueBBI, BBI.BrCond, true, true)) {
-      Tokens.push_back(new IfcvtToken(BBI, ICTriangleRev, TNeedSub, Dups));
+      Tokens.push_back(
+          llvm::make_unique<IfcvtToken>(BBI, ICTriangleRev, TNeedSub, Dups));
       Enqueued = true;
     }
 
     if (ValidSimple(TrueBBI, Dups, Prediction) &&
         MeetIfcvtSizeLimit(*TrueBBI.BB, TrueBBI.NonPredSize + TrueBBI.ExtraCost,
                            TrueBBI.ExtraCost2, Prediction) &&
         FeasibilityAnalysis(TrueBBI, BBI.BrCond)) {
       // Simple (split, no rejoin):
       //   EBB
       //   | \_
       //   |  |
       //   | TBB---> exit
       //   |
       //   FBB
-      Tokens.push_back(new IfcvtToken(BBI, ICSimple, TNeedSub, Dups));
+      Tokens.push_back(
+          llvm::make_unique<IfcvtToken>(BBI, ICSimple, TNeedSub, Dups));
       Enqueued = true;
     }
 
     if (CanRevCond) {
       // Try the other path...
       if (ValidTriangle(FalseBBI, TrueBBI, false, Dups,
                         Prediction.getCompl()) &&
           MeetIfcvtSizeLimit(*FalseBBI.BB,
                              FalseBBI.NonPredSize + FalseBBI.ExtraCost,
                              FalseBBI.ExtraCost2, Prediction.getCompl()) &&
           FeasibilityAnalysis(FalseBBI, RevCond, true)) {
-        Tokens.push_back(new IfcvtToken(BBI, ICTriangleFalse, FNeedSub, Dups));
+        Tokens.push_back(llvm::make_unique<IfcvtToken>(BBI, ICTriangleFalse,
+                                                       FNeedSub, Dups));
         Enqueued = true;
       }
 
       if (ValidTriangle(FalseBBI, TrueBBI, true, Dups,
                         Prediction.getCompl()) &&
           MeetIfcvtSizeLimit(*FalseBBI.BB,
                              FalseBBI.NonPredSize + FalseBBI.ExtraCost,
                            FalseBBI.ExtraCost2, Prediction.getCompl()) &&
         FeasibilityAnalysis(FalseBBI, RevCond, true, true)) {
-        Tokens.push_back(new IfcvtToken(BBI, ICTriangleFRev, FNeedSub, Dups));
+        Tokens.push_back(
+            llvm::make_unique<IfcvtToken>(BBI, ICTriangleFRev, FNeedSub, Dups));
         Enqueued = true;
       }
 
       if (ValidSimple(FalseBBI, Dups, Prediction.getCompl()) &&
           MeetIfcvtSizeLimit(*FalseBBI.BB,
                              FalseBBI.NonPredSize + FalseBBI.ExtraCost,
                              FalseBBI.ExtraCost2, Prediction.getCompl()) &&
           FeasibilityAnalysis(FalseBBI, RevCond)) {
-        Tokens.push_back(new IfcvtToken(BBI, ICSimpleFalse, FNeedSub, Dups));
+        Tokens.push_back(
+            llvm::make_unique<IfcvtToken>(BBI, ICSimpleFalse, FNeedSub, Dups));
         Enqueued = true;
       }
     }
 
     BBI.IsEnqueued = Enqueued;
     BBI.IsBeingAnalyzed = false;
     BBI.IsAnalyzed = true;
     BBStack.pop_back();
   }
 }
 
 /// AnalyzeBlocks - Analyze all blocks and find entries for all if-conversion
 /// candidates.
-void IfConverter::AnalyzeBlocks(MachineFunction &MF,
-                                std::vector<IfcvtToken*> &Tokens) {
+void IfConverter::AnalyzeBlocks(
+    MachineFunction &MF, std::vector<std::unique_ptr<IfcvtToken>> &Tokens) {
   for (auto &BB : MF)
     AnalyzeBlock(&BB, Tokens);
 
   // Sort to favor more complex ifcvt scheme.
   std::stable_sort(Tokens.begin(), Tokens.end(), IfcvtTokenCmp);
 }
 
 /// canFallThroughTo - Returns true either if ToBB is the next block after BB or